Thanks Gerald for the activation, the QSO and the clarification, which is indeed welcome, as I was in real doubt.
I saw the spot on SOTAwatch for G8CXK/P, went to the frequency, called, got picked up immediately and completed the QSO. I had already logged the QSO with the spotted station callsign but luckily I lingered for a little while on the frequency and soon I heard you CQing as GM4OIG/P. Then I saw on SOTAwatch a new spot with GM4OIG/P in the same frequency and summit as G8CXK/P.
Since the morse code sent by you sounded exactly the same as the one of the station I had the QSO with, I deleted the G8CXK/P callsing and wrote the right one instead, but I was in doubt thinking that it might have been a joint activation, I had the QSO with the initially spotted station and quickly you changed operator for whatever reason.
I was planning to check your activation log at some point to clear out my doubts, so this clarification is highly welcome.
Thank you again and HPE CU AGN SN.