It appears that the existing mortgage models will be used by mortgage lenders for at least the next year, quite possibly more. That's FICO 04 for EQ and TU (which was released in 2004) and FICO 98 for EX (which was released in 1998.
These are extremely old models that are likely less accurate than models that have been developed since then (but which were never permitted to be used by Fannie and Freddie, who control the mortgage industry). For example, FICO developed a whole new mortgage model in 2010 called the FICO 8 Mortgage Model (different from all the other other FICO 8 models) -- but as I say it was never used.
There's a bill in Congress, however, that would change all that. I include two links to that story below. If you are curious to see when the current models might one day be abandoned (and at some point they will be) you may want to occasionally google the name of that bill, which is the “Credit Score Competition Act.” (You could google that in January and then maybe twice a year.)
I have no idea whether that bill will pass or anything else about how long the current models will be used.
https://www.housingwire.com/articles/40901-senate-to-consider-bill-to-end-fico-monopoly-at-fannie-ma...
https://www.bloomberg.com/news/articles/2017-08-25/there-s-a-mortgage-monopoly-the-u-s-government-wa...
