PF1 is gonna be around for awhile yet, and I think it will be adapted to HLO long before it is played out.
That being said, HLC is still a good program while the App HLO is being improved and brought up to it's standard. It isn't going anywhere.

Just my two cents...

Not actually sure how many people are sticking with PF 1e as their game system. In several playtest groups, roughly half the people liked things and roughly half figured the original system was better than the release of a newer one.

Several of the kickstarter companies I back for campaigns/modules are still producing new content for PF 1e, but the largest of those (FGG) has mostly stopped support for PF 1e since they say D&D 5e and their own Swords & Wizardry are massively outselling the PF versions of their products; for several of those, there wasn't enough interest to be worth producing a PF version. They're still often putting the combat encounters of the creatures into a PF PDF for backers, so there is enough interest in that.

I'm not sure the numbers...

But if Hero Lab Online had Pathfinder 1e content available, our group would be subscribers and others out there too.
That way, HLC users would contribute the ongoing subscriptions to Lone Wolf, rather than having previously bought content but no longer be contributing revenue for the now discontinued (except for some 3pp publishers) system.

Lets calm down a bit, here. PF1 being transferred over along with other 3.5 OGL derivatives, like Mutants and Masterminds, isn't going to be a straight up build from scratch situation. The structure is there for the system already, with the framework from Starfinder and the building blocks that the App has already.

The main problem is using the Program's (HLC) information and adapting it to the App (HLO). My overall belief is that it isn't going to be keystroke by keystroke re-entering information from the files. The two products are still similar enough for HLO to adapt the info from HLC, likely being translated into the new App to use the newer proticals while still using the information within the original files.