@syrinxtech, your use of Time.isDST() will not produce the results you expect. That function simply returns true or false depending on where DST is in effect or not from a previous beginDST() or endDSt(). Establishing whether DST is in effect for a specific Photon in a specific timezone needs to be coded. @ScruffR posted this recently:
Another member used the google geolocation library to determine the devices position and then make a call to a website to get the DST offset. I need to find that post...
You may also want to reconsider using Arduino Strings due to their use of dynamic memory allocation. The many calls that will be made to createMsg() will slowly but surely make a mess of the heap memory. Using pre-allocated char buffer coupled with c-string commands will remove the dynamic allocation issue altogether. Nonetheless, thanks for the contribution!