For M2.2.x, we should use module M2 Pre Order version 1.0.9 instead of the current version as it is used for M2.3.x and above.
However, I notice that on this version, the Availability Date of the product doesn't show on the order confirmation email.
Please tell us how to add this information on email as it is necessary for our business?
On the old version 1.0.9, the module doesn't support the function of showing Availability Date on the order confirmation email.
To have this function, please edit files as below: