If so I head to XDA Forums and look around. Sometimes these are not updated even there. I have some 4.0 to 5.02 Android and most things are fine. I see on XDA steps for 5.0 Lollipop so there's that. Maybe you'll have to skip 4.x?
PS. Be sure to see if instructions such as http://grexas.blogspot.com/2014/10/upgradeupdate-lenovo-a10-70-a7600-to-50.html have been updated.
I have a Lenovo A10-70 tablet with 4.2 on it. Didn't know at the time that it wasn't 4.3 or 4.4.
I've been all over the Android forums trying to find how to update it to 4.2.