I am starting to think no IPads at all this year, (maybe a small chance during the Fall.) But Apple has no real incentive to upgrade the line-up more than they already have. I mean sure I really want iPad Pro 2, but it's not like the current Pro is slow or struggling with anything. Apple may treat the iPads like they did the MBP, iMac, and Mac Pro line-up during 2013-2015 (limited and incremental updates.)
Apple released a new budget iPad to boost sales and get more interest in the iPad market (which is what they truly wanted to do since iPad sales were dropping exponentially.)
I hope I'm wrong, but seeing that the usual keynotes for spring happen in March and we still have yet to get any true evidence of a keynote... (and even after months of rumors and "supposed" model number leaks of new iPads, has me thinking Apple is trying a different and new approach to the sale of iPads.)
Kallum.