So...we're now a third of the way through Congress and no legislation on this topic has been introduced. I think it's quite likely that we'll hit Jan 1st, 2019, see the works of 1923 turn public domain, and that'll cause a panic with copyright holders that might see the next Congress try to take action.
Doubtful that there will be an increase.
The Mickey Mouse Protection Act back in 1998 was presented as a way of harmonizing US copyright term with that of other countries, notably the EU. As it is, the US now has the longest copyright terms of any major country, especially on corporate works. The only significant exception is Mexico which has Life+100 years, but didn't increase the term for already copyrighted works when it extended the length back in 2003. TPP had threatened to increase copyright term for corporate works from 70 in most signatories to the lengthy 95 year term the US has, but that would have just made things worse elsewhere, not here and Trump scrapped TPP.
Plus, unlike 1998 there are major companies today whose business model is negatively impacted by lengthy copyright. You aren't going to see Apple, Facebook, or Google lobby Congress for longer copyright. They'll lobby to keep things as they are, or maybe even loosen copyright and reduce the term for corporate works from 95 to the 70 that the EU has.
Other countries have no interest in lengthening copyright term.