We don't have a lot of reservations tomorrow, so I think we'll be able to work in a relaxed manner then..
We don't have many clients who's made reservations for tomorrow, so we won't have to be in a rush during work.
ご質問ありがとうございます。
① "We don't have a lot of reservations tomorrow,"＝「明日は多くの予約は入っていない」
"so I think we'll be able to work in a relaxed manner then."＝「なので、ゆったりと働けると思う。」
② "We don't have many clients who's made reservations for tomorrow,"＝「明日、あまり予約をしたお客さんはいない」
"so we won't have to be in a rush during work."＝「なので、仕事中、バタバタしなくていい。」
☆予約の部分は現在形で、そして明日の部分は未来形 （we will be able to... ,
we will not have to...）になります。
ご参考までに。
We don't have many appointments tomorrow, so I won't be pressed for time when I'm working.
この場合、次のような言い方もできます。
ーWe don't have many appointments tomorrow, so I won't be so pressed for time when I'm working.
「明日はたくさん予約が入っていないから、働いている時、時間に追われない」＝「余裕を持って仕事ができる」
to be pressed for time で「時間に追われる・時間に縛られる」
ーThere aren't that many people coming in tomorrow, so I won't have to rush through my customers.
「明日はそんなたくさんの人が来ないから、お客さんを急いで終わらせなくて良い」
to rush through で「急いで終わらせる・仕事をさっさと片付ける」
ご参考まで！
アメリカ合衆国 
カナダ 
