Wedding gifts

Send out thank you cards asap.

I would recommend sending thank you cards now for the gifts you have already received. It'll be less that you have to write out later, and the people would know sooner rather than later that the gift was received.

You should absolutely send thank you cards as soon as you receive a gift.

We spent what should have been our wedding day writing thank you notes to people who had already got us gifts ( we postponed 5 days out, as our wedding was scheduled for mid-March when COVID hit). In my opinion it would be really rude to not write formal thank you notes in a timely manner. It's not like there's anything else occupying our time right now, you should spend an afternoon writing them.

I would send them thank you cards soon

Send thank you cards as you get the gifts. It keeps you from forgetting and prevents you from having to do a lot all at once. A verbal or text thank you is not a substitute for a thank you card.