The landlord and her son should check with their legal counsel to ensure they are taking all the required steps and providing the necessary notifications for the jurisdiction, but it is quite possible they will be able to take the actions they wish.

The tenant has access to me by snail mail, email and text.In order for the tenant to be in compliance with the lease, should I have received written notification by Feb 29 or is it acceptable for the notification to be dated by Feb 29 but delivered by snail mail at a later date?

A smart (and/or unscrupulous) tenant may actually ask you to increase their rent until the BK is discharged.If the tenant misses a payment, don't delay on eviction notifications and notify the BK court accordingly to protect your interests.  

@Brie SchmidtDepends on the type of stain if it will come out or not.  

Ie they assume it's grounded when it's not.

I don't see why not.  

While I'm 20yrs your senior, I'm not certain I qualify for the more mature label - definitely not if you were to ask my wife.In reading your post above, it would appear the significant short-term appreciation your property has experienced is a result of a frothy real estate market, rather than having acquired the property at a steep discount and/or forcing appreciation through improvement of the property. 

I was hoping to get around the need for a 25% down payment by getting an owner occupied loan, but after speaking with the mortgage provider, I was informed that the maximum 75% LTV applies whether the property is owner occupied or not.

If you sent it and it came back, if you have not opened it I would not.

I explained that I couldn't re-rent the apartment because, without notification from them that they had vacated, they were still the tenants.