Piles in the morning....

Question
We have recently adopted a lab mix from the local shelter.  At first, she was great about not relieving herself in the house.  The last two weeks, however, I have woken up to piles and puddles by the back door.  I know she wants to go out - but it's the middle of the night! I feed her at supper time, she goes out at bedtime.  But after that.....
Do you have any suggestioins?  Thank you!

Answer
By urinating/defecating at the back door, your dog is valiantly attempting to reach the appropriate spot (outdoors!)  Since you see (by her behavior) that she needs to eliminate after "bedtime", I suggest you change her feeding time (she should be fed twice daily, not once), feeding her half a portion in the early AM and half late afternoon, so her need to defecate is within the parameter of time you allocate to taking her out.  Also, remove water (unless she is ill, it is very hot or she has heavily exercised, which shouldn't happen late in the day anyway) at about 7PM (or within four hours of your retiring for the night.)  TAKE HER OUT for the next several weeks and REWARD/PRAISE her appropriate elimination, to solidify her house training skills.  Be certain she has fair outings, five a day at least, and give her time to perform her bodily functions out there. Prevent her accidents by allocating her food schedule and water according to the biological schedule she is naturally following. And give it time.