Mud Swallow Nest Construction

There is a bird building a nest out of mud on the ceiling of our front porch.  This is an abbreviated study in the process:

Day 1? (or when I first noticed):

Day 7

 Day 14:

(i'll add to this post if i remember to take more photos.)
* as promised updates on 2/23:

Day 20:

Day 27:

Do the last two even look different?  Perhaps this is just another construction start that could not secure the next round of funding.  I'll leave this little project for now and let you know if things pick back up.