Reach for ～かたがた in formal written Japanese — business letters, greeting cards, seasonal correspondence — when a single visit or communication serves two purposes at once. The noun before かたがた names the socially-framed pretext (greeting, thanks, report), and the clause that follows states what else you are accomplishing by the same act. It is markedly stiff and epistolary; in speech you would use ～を兼ねて or ～ついでに instead.