AC leaking into drip pan in the attic
The laws of physics cannot be ignored, water doesn't flow up hill...
If the condensation is building up in the pipe to where is drips out of the top of that first Tee fitting, it means it is not flowing out to the outside. Either something is still blocking that pipe, or the pipe is going up hill. How long is that pipe going outside? If it's relatively short, try running a sink snake through it to see if mold or animal nests have blocked it.