A year attached to a shirt can help organise a collection. It does not answer every question about the object represented by a photograph.
Identification
Record the team and season as stated by your source. If the source uses a date range, preserve it. When you have not checked it against a reliable independent reference, say so.
Observation
Keep visible details separate: a collar shape, a colour arrangement, a printed name or a stitched edge. An observation describes what is present in the particular reference, not every shirt associated with that season.
Provenance
Manufacturing origin, ownership history and match use need their own supporting material. A familiar design is not a substitute for that evidence. A careful archive leaves room for an unanswered question and a later correction.