Travelling to Japan and can’t take Amfexa or have enough time to switch prescription. advice for withdrawals?

Anyone have any advice on dealing with amfexa withdrawals? I have ten days there, and I regularly take 3 x 20mg daily. I have some 40mg Medikinet capsules left over from a few months back, still in the foil. Wondering if I should cold turkey it or try and take those instead, it’s under the amount required to declare for the trip. Before I’ve had horrible hypersomnia on amfexa withdrawals and I’m worried about it ruining the trip.