Elvis,
I think you're correct, you will only "need" 25 more hours before you reach the minimum for the PPL. As for how long it will actually take - I'd be quite surprised if your previous experience will reduce the time it would take to get the PPL. After a 5 year break, I suspect that although you'll remember much of the theory, many of the instincts that a 20-hour pilot has built up will have departed you.
On the bright side, though, I don't think people like insurance companies look into how recently you've logged your time, as long as you're reasonably current. So you should be able to get a PPL about 45 hours from now, with a total time of 65 hours. That means that you'll only need another 35 hours before insurance companies and the like will insure you as a 100-hour pilot and give you much lower rates than a 50-hour new PPL!
FFF
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