This is what I have so far adapted from here which now appears to work. Will save here for others that may need it
notify on public ip change (flow) - Node-RED
[{"id":"ba4e3fc7.00842","type":"function","z":"918f24fc.64fb28","name":"Compare Status","func":"var laststatus = msg.laststatus;\nvar currentstatus = msg.payload.status;\nmsg.currentstatus = currentstatus;\nmsg.topic = \"stable\";\nif (laststatus !== currentstatus) {\nmsg.payload.status = currentstatus;\nmsg.topic = \"new\";\n}\n\nreturn msg;","outputs":"1","noerr":0,"initialize":"","finalize":"","x":180,"y":290,"wires":[["8e5460f6.3581","d033bfb7.998fb"]]},{"id":"8e5460f6.3581","type":"template","z":"918f24fc.64fb28","name":"Description","field":"payload","fieldType":"msg","syntax":"mustache","template":"Your {{topic}} Status {{payload.status}}","x":345.00006103515625,"y":287.90869140625,"wires":[["cc894df1.59888","1af0d7ac.896358"]]},{"id":"cc894df1.59888","type":"switch","z":"918f24fc.64fb28","name":"","property":"topic","propertyType":"msg","rules":[{"t":"eq","v":"stable","vt":"str"},{"t":"else"}],"checkall":"false","repair":false,"outputs":2,"x":481.00006103515625,"y":286.9996032714844,"wires":[["ab6f0222.cca5b"],["b54a11ef.78f15","a0a382d5.207bd","e15b5c1c.f3b87","6618288.4d352d8"]]},{"id":"b54a11ef.78f15","type":"function","z":"918f24fc.64fb28","name":"prepare","func":"var newFile = {};\nnewFile.filename = msg.filename;\nnewFile.payload = msg.currentstatus;\n\nreturn newFile;","outputs":"1","noerr":0,"initialize":"","finalize":"","x":649.000244140625,"y":290.9996032714844,"wires":[["9322e06.f42442","5bfb5444.f0a32c"]]},{"id":"bac29017.418d2","type":"link out","z":"918f24fc.64fb28","name":"","links":["c820407a.3b6d7"],"x":1335,"y":90,"wires":[]},{"id":"c820407a.3b6d7","type":"link in","z":"918f24fc.64fb28","name":"","links":["bac29017.418d2"],"x":65,"y":290,"wires":[["ba4e3fc7.00842"]]},{"id":"a2c2c3f7.5586a","type":"switch","z":"918f24fc.64fb28","name":"Home / Away","property":"payload.presence","propertyType":"msg","rules":[{"t":"eq","v":"HOME","vt":"str"},{"t":"eq","v":"AWAY","vt":"str"}],"checkall":"true","repair":false,"outputs":2,"x":980,"y":100,"wires":[["541a37bd.c70c38","83c73f23.bf476"],["28552236.ea91de","95b97372.24931"]]},{"id":"28552236.ea91de","type":"change","z":"918f24fc.64fb28","name":"Away","rules":[{"t":"set","p":"payload.status","pt":"msg","to":"AWAY","tot":"str"},{"t":"delete","p":"payload.presence","pt":"msg"},{"t":"delete","p":"payload.presenceLocked","pt":"msg"}],"action":"","property":"","from":"","to":"","reg":false,"x":1140,"y":110,"wires":[["bac29017.418d2","1be6da1c.1553c6"]]},{"id":"541a37bd.c70c38","type":"change","z":"918f24fc.64fb28","name":"Home","rules":[{"t":"set","p":"payload.status","pt":"msg","to":"HOME","tot":"str"},{"t":"delete","p":"payload.presence","pt":"msg"},{"t":"delete","p":"payload.presenceLocked","pt":"msg"}],"action":"","property":"","from":"","to":"","reg":false,"x":1140,"y":70,"wires":[["bac29017.418d2","aea37c87.d3736"]]},{"id":"d033bfb7.998fb","type":"debug","z":"918f24fc.64fb28","name":"6","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":150,"y":340,"wires":[]},{"id":"1af0d7ac.896358","type":"debug","z":"918f24fc.64fb28","name":"7","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":310,"y":340,"wires":[]},{"id":"a0a382d5.207bd","type":"debug","z":"918f24fc.64fb28","name":"8","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":470,"y":340,"wires":[]},{"id":"ab6f0222.cca5b","type":"debug","z":"918f24fc.64fb28","name":"No Change","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":660,"y":250,"wires":[]},{"id":"9322e06.f42442","type":"debug","z":"918f24fc.64fb28","name":"10","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":640,"y":340,"wires":[]},{"id":"bcc5cdeb.4d378","type":"inject","z":"918f24fc.64fb28","name":"AWAY","props":[{"p":"payload.presence","v":"AWAY","vt":"str"},{"p":"payload.presenceLocked","v":"false","vt":"bool"},{"p":"topic","vt":"str"},{"p":"filename","v":"homeaway.json","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"getState","x":500,"y":210,"wires":[["50725d7e.d7e9d4","a2c2c3f7.5586a"]]},{"id":"aea37c87.d3736","type":"debug","z":"918f24fc.64fb28","name":"3","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":1370,"y":50,"wires":[]},{"id":"83c73f23.bf476","type":"debug","z":"918f24fc.64fb28","name":"1","active":false,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":1140,"y":20,"wires":[]},{"id":"95b97372.24931","type":"debug","z":"918f24fc.64fb28","name":"2","active":false,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":1140,"y":160,"wires":[]},{"id":"1be6da1c.1553c6","type":"debug","z":"918f24fc.64fb28","name":"4","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":1370,"y":130,"wires":[]},{"id":"f480def5.c9e08","type":"debug","z":"918f24fc.64fb28","name":"H","active":false,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":640,"y":170,"wires":[]},{"id":"50725d7e.d7e9d4","type":"debug","z":"918f24fc.64fb28","name":"A","active":false,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":640,"y":210,"wires":[]},{"id":"868fd5a.2bf0728","type":"inject","z":"918f24fc.64fb28","name":"HOME","props":[{"p":"payload.presence","v":"HOME","vt":"str"},{"p":"payload.presenceLocked","v":"false","vt":"bool"},{"p":"topic","vt":"str"},{"p":"filename","v":"homeaway.json","vt":"str"},{"p":"laststatus","v":"HOME","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"getState","x":500,"y":170,"wires":[["f480def5.c9e08","a2c2c3f7.5586a"]]},{"id":"5bfb5444.f0a32c","type":"file","z":"918f24fc.64fb28","name":"writeFile","filename":"","appendNewline":false,"createDir":false,"overwriteFile":true,"x":820,"y":290,"wires":[["51a7cc81.94ba64"]]},{"id":"51a7cc81.94ba64","type":"debug","z":"918f24fc.64fb28","name":"12","active":false,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":810,"y":340,"wires":[]},{"id":"6618288.4d352d8","type":"debug","z":"918f24fc.64fb28","name":"Change","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":650,"y":440,"wires":[]}]
