Firebase Amphibious Transport Upgrade causes NAN

ERROR: The following variables are NaN! Please report this.
$$SF.CreditsInvested

If you upgrade Amphibious Transport in the Firebase it will cause a NaN issue for CreditsInvested. Problem is on:

[[Upgrade Amphibious Transport|Firebase][$SF.Upgrade = 1, $SF.Colonel.Talk += 1, $SF.Squad.HAT++, $SF.CreditsInvested += (_cSub), cashX(forceNeg(_cHAT), "specialForcesCap")]]

It should be $SF.CreditsInvested += (_cHAT)