The Donegal County Board has been contacted by Croke Park over claims that the county's senior team held a training camp for its squad at the end of April.
It was reported in the national media last week that Donegal is one of a number of counties that have been asked to explain reports that they held training camps last month - something that's no longer allowed under the new April club rule.
A Donegal County Board spokesperson has confirmed to Tuesday's Donegal Democrat that Donegal is one of a number of counties written to by GAA officials in Croke Park. Mayo, Armagh, Tyrone and Dublin were also reported to have been contacted on the issue.
Donegal's situation relates to reports that the county's senior panel attended a training camp in Belfast on the last weekend in April - two weeks before their championship opener against Cavan.