This is because 4.4 seems to have made you use the same ZOOM value on Calc for all tabs in a spreadsheet. This is no good to me and the previous (before upgrade to Version: 4.4.5.2
Build ID: a22f674fd25a3b6f45bdebf25400ed2adff0ff99
Locale: en_GB) version did not have this behaviour. I have not seen anyone else ask about this so easiest option is to downgrade.
Thanks