What is the better thank you message, after user submits contact request?

After user submits some question or suggestion on the contact page he is redirected to the "Thank you page".

Which is the better way to say thanks and tell how soon will they get their reply? (we, unfortunately, can't say the exact time, because for working days it's up to an hour, but on weekdays and bank holidays it might take up to several days to get a response.)

Thank you for contacting us, we will get back to you as soon as possible.

Thank you for contacting us, we will reach back to you in a short time.

Thank you for getting in touch, we will get back to you as soon as possible.

Thank you for getting in touch, we will reach back to you in a short time.