Much better now. Well done. Now it is easier to provide some suggestions.
Check if the revised nodes work well now.
[{"id":"c23faefa.34bc7","type":"tab","label":"Flow 1","disabled":false,"info":""},{"id":"2a694971.719046","type":"template","z":"c23faefa.34bc7","name":"{\"fmode\":2}","field":"payload","fieldType":"msg","format":"json","syntax":"mustache","template":"{\"fmode\":0}","output":"json","x":270,"y":100,"wires":[["e8c7847a.da2da8"]]},{"id":"3987e9df.770006","type":"inject","z":"c23faefa.34bc7","name":"AUTO","topic":"","payload":"0","payloadType":"num","repeat":"","crontab":"","once":false,"onceDelay":0.1,"x":90,"y":260,"wires":[["1ed828f8.624227"]]},{"id":"5c9f7e9f.87101","type":"inject","z":"c23faefa.34bc7","name":"ON","topic":"","payload":"2","payloadType":"num","repeat":"","crontab":"","once":false,"onceDelay":0.1,"x":90,"y":300,"wires":[["1ed828f8.624227"]]},{"id":"1ed828f8.624227","type":"change","z":"c23faefa.34bc7","name":"fmodeUpstairsSet","rules":[{"t":"set","p":"fmodeUpstairsSet","pt":"flow","to":"payload","tot":"msg"}],"action":"","property":"","from":"","to":"","reg":false,"x":250,"y":260,"wires":[["e3bbd124.13fee"]]},{"id":"b4c6bbed.4ed288","type":"change","z":"c23faefa.34bc7","name":"revised2","rules":[{"t":"set","p":"fmode","pt":"msg","to":"fmodeUpstairsSet","tot":"flow"},{"t":"set","p":"payload","pt":"msg","to":"{\"fmode\" : fmode}","tot":"jsonata"}],"action":"","property":"","from":"","to":"","reg":false,"x":440,"y":340,"wires":[["e9397e36.895ef"]]},{"id":"d4c51efd.e2ec6","type":"function","z":"c23faefa.34bc7","name":"revised3","func":"msg.payload = {fmode: flow.get(\"fmodeUpstairsSet\")}\n\nreturn msg;","outputs":1,"noerr":0,"x":450,"y":380,"wires":[["fc8df22b.a27"]]},{"id":"a6852b8d.66f828","type":"inject","z":"c23faefa.34bc7","name":"AUTO","topic":"","payload":"","payloadType":"date","repeat":"","crontab":"","once":false,"onceDelay":"","x":90,"y":100,"wires":[["2a694971.719046"]]},{"id":"e3bbd124.13fee","type":"template","z":"c23faefa.34bc7","name":"revised1","field":"payload","fieldType":"msg","format":"json","syntax":"mustache","template":"{\"fmode\":{{flow.fmodeUpstairsSet}}}","output":"json","x":440,"y":300,"wires":[["7b867e.3d569984"]]},{"id":"856f0381.1e481","type":"comment","z":"c23faefa.34bc7","name":"Working","info":"","x":260,"y":60,"wires":[]},{"id":"cc9ebd54.c81ab","type":"comment","z":"c23faefa.34bc7","name":"???","info":"","x":250,"y":220,"wires":[]},{"id":"f27bcd77.2233","type":"debug","z":"c23faefa.34bc7","name":"{\"fmode\":2}","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","x":530,"y":140,"wires":[]},{"id":"7b867e.3d569984","type":"debug","z":"c23faefa.34bc7","name":"{\"fmode\":\"{{flow.tmodeUpstairsSet}}\"}","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","x":950,"y":300,"wires":[]},{"id":"e9397e36.895ef","type":"debug","z":"c23faefa.34bc7","name":"Set fmodeUpstairsSet","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","x":900,"y":340,"wires":[]},{"id":"fc8df22b.a27","type":"debug","z":"c23faefa.34bc7","name":"var msg = {fmode: flow.get(\"fmodeUpstairsSet\")}","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","x":990,"y":380,"wires":[]},{"id":"3905345a.2a600c","type":"template","z":"c23faefa.34bc7","name":"{\"fmode\":0}","field":"payload","fieldType":"msg","format":"json","syntax":"mustache","template":"{\"fmode\":2}","output":"json","x":270,"y":140,"wires":[["f27bcd77.2233"]]},{"id":"eca3a052.69663","type":"inject","z":"c23faefa.34bc7","name":"ON","topic":"","payload":"","payloadType":"date","repeat":"","crontab":"","once":false,"onceDelay":"","x":90,"y":140,"wires":[["3905345a.2a600c"]]},{"id":"e8c7847a.da2da8","type":"debug","z":"c23faefa.34bc7","name":"{\"fmode\":0}","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","x":530,"y":100,"wires":[]},{"id":"7cdee0f1.f8aec","type":"inject","z":"c23faefa.34bc7","name":"AUTO","topic":"","payload":"0","payloadType":"num","repeat":"","crontab":"","once":false,"onceDelay":0.1,"x":90,"y":340,"wires":[["665cd1d7.28e1e"]]},{"id":"f1c5e8cb.c7c6b8","type":"inject","z":"c23faefa.34bc7","name":"ON","topic":"","payload":"2","payloadType":"num","repeat":"","crontab":"","once":false,"onceDelay":0.1,"x":90,"y":380,"wires":[["665cd1d7.28e1e"]]},{"id":"665cd1d7.28e1e","type":"change","z":"c23faefa.34bc7","name":"fmodeUpstairsSet","rules":[{"t":"set","p":"fmodeUpstairsSet","pt":"flow","to":"payload","tot":"msg"}],"action":"","property":"","from":"","to":"","reg":false,"x":250,"y":340,"wires":[["b4c6bbed.4ed288"]]},{"id":"9492797a.598f98","type":"inject","z":"c23faefa.34bc7","name":"AUTO","topic":"","payload":"0","payloadType":"num","repeat":"","crontab":"","once":false,"onceDelay":0.1,"x":90,"y":420,"wires":[["acab3ccc.91052"]]},{"id":"acab3ccc.91052","type":"change","z":"c23faefa.34bc7","name":"fmodeUpstairsSet","rules":[{"t":"set","p":"fmodeUpstairsSet","pt":"flow","to":"payload","tot":"msg"}],"action":"","property":"","from":"","to":"","reg":false,"x":250,"y":420,"wires":[["d4c51efd.e2ec6"]]}]
Edit : below node should work too. It reads the value from flow context using JSONata.
[{"id":"53045596.a5f5bc","type":"change","z":"c23faefa.34bc7","name":"revised4","rules":[{"t":"set","p":"payload","pt":"msg","to":"{\"fmode\" : $flowContext(\"fmodeUpstairsSet\")}","tot":"jsonata"}],"action":"","property":"","from":"","to":"","reg":false,"x":440,"y":340,"wires":[["e9397e36.895ef"]]}]
Probably there are many other variations.