Max Tech on YouTube is really trying to push this idea of a (non-Pro) iMac coming next month.
I just think that makes no sense UNLESS the iMac Pro starts at say $3,000. Otherwise you release a (non-Pro) iMac at ~$2,000 next month and then an iMac Pro at $2,500 in June? No way. $500 isn't chump change but you are just gonna anger a lot of buyers of the (non-Pro) iMac in that scenario.
I believe Ross Young is absolutely correct with the iMac Pro coming at WWDC. So that means we either get that model as the only 27" iMac model, starting at ~$2,500. OR, we do get that (non-Pro) iMac either in March or WWDC at ~$2,000 and then the iMac Pro starting at ~$3,000. I don't think any other scenario for the model makes sense.