My recent experiences with RF lenses and Adorama have been...
* I have ordered the 100-500 December 31 2020 and received it January 21 2021 (21 days)
* I have ordered the 50 1.2 March 18 2021 and received it April 8 2021 (21 days)
* I did pre-order the RF 100 macro when announced (April 14 2021) and just got an email from Adorama that they are shipping mine to me today

I assume that the 100 macro is less exotic than the others and more available generally speaking, but still happy about that.
So I guess I have been lucky? Let me tell you that Broncolor stuff takes way longer... even modifiers with no electronic parts whatsoever!