I honestly do not see any contradictions.
AFAIK, the document to which I linked above was new as of Feb 8 (yesterday), and it says that testing is "mandatory before arrival, upon arrival and during the Championships week."
I think that you are referring to the event announcement, which was revised on
Feb 5.
The section of the announcement pertaining to COVID (on p. 9) refers to the "Event Health Regulations" -- without spelling out all the requirements of the regulations.
(And I see no statement anywhere in the announcement that rules out additional requirements for subsequent testing after the pre-arrival test.)
19. Covid-19
... The Event Health Regulations and information sent to the ISU Members must be strictly followed by every Event Attendee. ...
The section of the announcement pertaining merely to
registration (on p. 7) says that the Event Health Regulations must be followed AND that a negative pre-arrival test is required. (Again, there is nothing that says that the pre-arrival test is the only testing requirement in the regulations.)
10. REGISTRATION
PCR Testing prior to registration
All event attendees must follow the Event Health Regulations and must make sure to have a negative Covid-19 PCR test result prior to arriving in Stockholm.
... All Competitors and Judges will be required to present their passport ... prior to receiving accreditation, as well as the negative Covid-19 PCR Test result(s). ...