What @grizzman said. They did away with the original standard gas port and made their RGP the new “standard,” with the ERGP still being the ERGP. I did measure mine, and a 1/16" drill bit fit snugly as I recall, which makes it a .0625". I’ve never had any issues with reliability whatsoever, FWIW. One of mine gas a BRT 0.057" gas tube and runs a dedicated direct threaded can with an A5H2. The other has a standard gas tube and runs an OSS 5.56 can with an A5H3.
ETA: I’ll pull one of the gas blocks and measure it again, just to make sure I’m not misremembering.