As I  understand it..... please correct me if I'm wrong ..... US Tax losses must clear before the end of the year. The last day of trading (for clearing)  in the US is Monday Dec, 31 and that would be the clearing day for trades on Wednesday 12/26.....

So tax loss selling of RAMPH in the US should be over with the close of trading 12/26.....

Canadians tax loss selling must be accomplished by 1:00 PM when the TSX closes on Dec 24th.