Hi, well my dad has a bond with immigration...

There is not enough information to answer your question. Think about making an appointment with an immigration attorney to figure out if your father is eligible to adjust status (criminal record? Manner of entry into the US?). If he is eligible you should file right away. Good Luck.

Assuming everyone qualifies and there are no criminal history issues, they should file as soon as they can.

Assuming he is eligible you should begin the process as soon as possible as it can take some time to process. You should consult with an immigration attorney to determine eligibility and ensure there are no problems you are not aware of; further, an attorney can assist with the Courts in either continuing the case to allow for the adjustment to be processed or, perhaps, seeking to have the case closed altogether based on prosecutorial discretion.

If your father have no criminal record and he is eligible, then yes you can file any time you want.