Mup verifies on wrong port

help
1

After successful deployment with mup for some time and some updates (not in mup.js) I have the following problem.
I am deploying to port 4000
env: {
…
PORT: ‘4000’,
}
The deployment goes without errors but in the verification phase I get
x Verifying Deployment: FAILED

      ------------------------------------STDERR------------------------------------
        % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed

0 0 0 0 0 0 0 0 --:–:-- --:–:-- --:–:-- 0curl: (7) Failed to connect to 172.17.0.3 port 3000: Connection refused
…

Container spent too much time restarting.
=> Logs:
=> Starting meteor app on port:3000
Meteor requires Node v12.0.0 or later.

I do not use Port 3000 in mup.js

Here is some info on my environment:
In mup.js:
mongo: {
port:27017,
version: ‘3.4.1’,
servers: {
one: {}
}
},
docker: {
image: ‘abernix/meteord:node-8.4.0-base’
}
deployCheckWaitTime: 120,

System:
Ubuntu 16, mup 1.5.3, Meteor: 1.10.2, node 12.20.0, npm 6.14.8

2

According to the MUP docs PORT needs to be numeric.

3

No, I changed the line in mup.js to

PORT: 4000,

and have run mup setup, but the error message remains the same.