I put the clothes I would need in my bag for the time between sending my things and the time I check out.
この場合、次のような言い方ができますよ。
ーI put the clothes I would need in my bag for the time between sending my things and the time I check out.
「身の回りのものを送ってからチェックアウトまでの間のため、必要な洋服をかばんに入れた」
for the time between A and the time B で「AからBまでの間」と言えます。
ご参考まで!