I checked with server gods and they assured me that they will migrate the older 5.6 php to new machine. A great load off my mind.
So, with that in mind, when I do have php7 for everything else, are there any issues (besides cart) that I need to know once server transitions? My most used WA is data assist and cart. Before I migrate, is there anything I need to know/change? Remember that I ran into issues when mysql went to MariaDB and caused a number of unforeseen problems. I don't want to migrate until I fully understand what I need to look for. (Color me "scared!")