I've just noticed that Alamy has introduced hybrid licensing for shots, offering a controlled usage 5-year licence and a standard unlimited RF licence on all RF images.
At least it blows away the nonsense about RF and RM being fundamentally in conflict in some way.

I don't know that the naming is right - royalty free isn't really what the following terms map to IMO - but from my three sales in January, here are the two variants called "royalty free"  but limited by use and time:

Country: Worldwide
Usage: Non-Editorial Electronic and web uses, Use on website and social media, worldwide for 5 years.
Media: Corporate website, single design

Usage: iQ sale: Magazine, Editorial print and digital use. Up to DPS, inside.One time use only

The other RF sale was the largest amount - it certainly seems reasonable to offer fewer rights for less money if they have a market for that.

The only problem with the limited rights sales is tracking that buyers don't overstep their licensed rights (something that Canva neatly avoids). I can't imagine Alamy really pays much attention to that unless a contributor brings it to their attention.

My guess is that they are calling the five-year licenses RF because it is against their rules for the same image to be offered both RF and RM

Where are they calling the 5 years licenses RF ? I do not believe that they are.

Images which are primarily offered under RM are only being offered under RM (including simple off-the-peg 5 year licenses). Images offered under RF are also available under various more specific 5 year (off-the-peg RM) licenses.

Yes they are, it's in the sales report

In the contributor accounting. But they are not selling 5 year licenses as RF, are they ? (The 5 year license, by definition, is not RF.)

I am sure that 'Royalty Free' in your contributor accounting is a reference to the fact that the image has primarily been offered as RF. But the accounting page has become somewhat ambiguous because the 5 year license actually isn't RF. ie the accounting page has not been updated since the time when images offered as RF were only offered as RF.

All of my content at Alamy is RM only. I have sold 5 year licenses and even in the accounting these all show as Rights Managed. Not RF.

They're either selling 5-year licenses as RF

They are not selling 5 year licenses as RF. The 5 year licenses are not RF by definition - and underneath each image it says - "or choose a royalty-free license" / "or choose a rights-managed license" - respectively, depending upon how the image has primarily been offered.

But let's be 100% clear. Content which is primarily (only) listed as RM is not also being sold RF. It is only that content sold as RF is also available via a less costly pr�t-�-porter 5 year licence - which is therefore RM, by definition.

or they are selling images as both RM and RF at the same time, which is something they used to say could never happen.

I did not know that they had ever specifically said this. I know that they have said that content which is being sold as RF elsewhere cannot be primarily listed as RM with them. And that makes sense because it protects the RM customer. And - RM content is not being sold RF.

I do not believe that there is any discrepancy apart from that the contributor accounting page says "royalty free" - somewhat ambiguously referring to the original listing of the image rather than the specific license.