since you have the "V" model, I have to assume you are blessed with mother Verizon.
go to System Updates, and set it to Upgrade via Wifi only....
Now, make darn sure that you never, ever, use WiFi again.....
that will stall it off for a very long time....
My VZW phone never did download 5.0 until last week when in a fit of stupidity, I turned ON WiFi and "oops!" it started downloading 5.0
I jerked the battery out before it made 50%..... System Updates states that my phone has two (2) failed attempts to download the Update to LolliFlop. It has not once, offered to try and download the rest of it.... I am going to leave it alone at 50% downloaded.... I still have way more free space than I ever will need, I put all extraneous stuff on the 64 gB extSDcard anyway.
My daughter and I are on the same 3 gB/month plan and we have never gone over the limit.
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2 ea. Verizon Galaxy S5, 4.4.4 forever!, ART
MyPhoneExplorer lets you access a broken phone while locked
Nova Prime, Textra, Blue Mail, Qi wireless equipped
MacroDroid can help extend battery life
MacroDroid senses Screen off, turns Wifi & Data OFF
MacroDroid senses Screen UnLock, turns Data ON
PureVPN when using a public WiFi