Running command via ssh while reading from a file ends the file reading

Question

I have, very generally speaking, a bash script that reads some configuration data from a CSV file and performs an rsync backup.

#!/bin/bash

while IFS="," read -r share source type subdir rsyncPath
do
  # Run preflight script for share
  [ -f "$share.preflight" ] && $share.preflight

  # Now run some rsync command to backup the data
done < <(grep -P -v '^\s*#' "inputfile")

The inputfile consists of lines like this:

Info,user@remotehost:/share,,,/usr/bin/sudo /opt/bin/rsync
docker,user@remotehost:/share,,,/usr/bin/sudo /opt/bin/rsync

There are additional preflight scripts present:

docker.preflight:

#!/bin/bash
ssh user@remotehost 'echo Stopping docker service'

Info.preflight:

#!/bin/bash
echo "Hello Info.preflight"

In this example, the script reads both lines from the inputfile and performs each preflight script:

+ IFS=,
+ read -r share source type subdir rsyncPath
++ grep -P -v '^\s*#' shares
+ '[' -f ./Info.preflight ']'
+ ./Info.preflight
Hello Info.preflight
+ IFS=,
+ read -r share source type subdir rsyncPath
+ '[' -f ./docker.preflight ']'
+ ./docker.preflight
Stopping docker service
+ IFS=,
+ read -r share source type subdir rsyncPath
+ echo Done.
Done.

But if I switch the order and put the docker line first, the docker.preflight script is run and then the read loop ends, even though there is more input to consume.

+ IFS=,
+ read -r share source type subdir rsyncPath
++ grep -P -v '^\s*#' ./inputfile
+ '[' -f ./docker.preflight ']'
+ ./docker.preflight
Stopping docker service
+ IFS=,
+ read -r share source type subdir rsyncPath
+ echo Done.
Done.

Can anyone shed a light on what is going on here? How does runnign ssh interfere with my read loop?