Posting this after a facebook post on someone here in NEO looking for PCC matches and not finding any. Here's what I've learned to date, feel free to update it with more information.
Common to all is that you must have an empty chamber indicator (ECI or chamber flag) in it when not shooting.
Steel Challenge or other steel matches (Ed's Steel at Crooked Creek) that I've found all allow pistol caliber carbines to be used. I've shot both a 10mm TNW ASR and an AR9 at South Cuyahoga's steel matches. At South Cuyahoga I carried it slung not sure about any of the others.
BASS at Stonewall this year is now allowing PCC. Keep it cased until it's your turn. I believe you will shoot last though, after all the handguns. And then you'll do one alley/stage after another so only one PCC is uncased at a time. Try to be kind and have enough magazines loaded up when you go up for your turn.
PCSI, FCSC (Wauseon), ARO/NEO Shooters for USPSA - All of these clubs are allowing the new PCC division at their matches. I understand at PCSI you can uncase in the safe area if you want to carry it slung. They also have rifle racks at the bays to store them when you aren't shooting if you've uncased it. FCSC is having you keep it cased. I was the first PCC they had a few weeks ago and they had me keep it cased until I was up and at the starting position. After unload & show clear, it was recased.
ALGC - I've heard that Ashland Lake will be allowing PCC for their IDPA matches. It will follow the rules from an initial 2017 rulebook although they were taken out of the final one. While optics are allowed, you will be limited to 10 in the magazine (start with 10 in the magazine and one chambered). I have not confirmed this yet by shooting a match in PCC yet. Hopefully sometime this summer though.
Who else here is looking to shoot PCC this year? If you've already done so, how about sharing your experience?