There's no lifetime subscription...just the 6 or 12 month deals that I mentioned before.

Some scam sites might offer a 'lifetime' deal, but if you buy from a scam site you won't be entitled to any updates or support from the official site. You might also end up with a crappy version of LW.

Q: How much does LimeWire cost?
A: LimeWire BASIC is completely free to download and use. An enhanced version of LimeWire, LimeWire PRO, is also available for a one time charge. LimeWire PRO can be purchased as an electronic download only.
LimeWire is a software application. The one-time payment for LimeWire PRO is a payment to purchase a copy of the program. PRO purchasers also receive Technical Support via email and up to 6 months of free updates.
You will not be charged again by Lime Wire after your initial purchase. After 6 months, PRO users have the option to purchase an additional 6 months of technical support and free updates for a reduced price.

From what I gather out of this is: Techsupport is purchased for 6 or 12 months. Limewire pro that I purchased for 39 dollars should still be active, right?

If you buy Pro (from the official site) for 6 months, you're entitled to tech support & free updates for 6 months. Likewise if you bought Pro for 12 months. ..benefits expire after 12 months.

You said "It's been a long time ago since the purchase"...how long? Check your CC statement for when you bought Pro...who is the vendor that shows up next to your payment?

Pro doesn't even cost $39 now...if you paid $39 a long time ago then you must've bought Pro from a scam site.
Some scam sites can rediredt you to the official site to download Pro, once you've paid. But that doesn't mean that you've bought from the official site.