@ixamnis.. worry not. this is all very routine and doable.
FTM support got to answer first .. and hit the points. but i will echo / call out 3 things...
#1) before you upgrade,
a) Register your old phone to an email (
Edited: on iPhone - > option > register on Andorid register on admin web site )
b) Export your old phone data (stores entire database on iscore servers)
c) be sure to Write down your old phone Customer ID number.
all three steps a,b,c IMPORTANT for future flexibility….
#2) If you old phone can survive in wi fi only mode. bingo, you have a solution for your original question about a master data storage unit for lifetime stats (old device) .
you can store lifetime stats on old the device (if it can survive in wi fi mode without cell service), and can use your new device fresh for college years. (you can transfer college games back to master 'lifetime stats' device as you go through college). this will make exporting faster. .
If your old phone can not survive in wifi only mode, the original question you posed on having a second storage device is still an item to discuss/resolve.
however, you may find your new device has better processing and connectivity power and the long export that concerns you may be less an issue now. and you could simplify everything by keeping all your data (lifetime) on your new device.
#3) regardless of number 2.. you probably should familiarize your self with some features described in FAQs from iScore web site
http://iscoresports.com/baseball/support.php
Specifically …
* I got a new device. How do I transfer my old data to the new device?
http://iscoresports.com/baseball/kb/faq ... lldata.php
* I have multiple devices. Can I score on any device throughout the season and still have all the stats accumulate?
http://iscoresports.com/baseball/kb/faq ... _share.php
* How do I transfer my Team Website to another device?
http://iscoresports.com/baseball/kb/faq ... device.php
Feel free to post back as you think of more questions or concerns