Moving several files to different folders with same name - shell

Question

I have some data for several stations that are separated for the station they are in, and the day they were recorded, so for station 1, for example, I have multiple folders called 2019.001,2019.002 etc. and inside these folders I have the files (all with the same name) ending with HHZ. What I have done is getting these files from each of the stations and putting them on another folder while renaming them to have the name of the folder above and maintaining the name of the station, afterwards I created the folders corresponding to their names. My actual question is how to move the files that correspond to the same day, e.g. 2019.001.station1 and 2019.001.station2 to the folder 2019.001.
dir0=`pwd`
mkdir -p data || exit 1
for pathname in $dir0/stam/*/*HHZ; do
cp "$pathname" "data/$( basename "$( dirname "$pathname" )" )STAMHHZ"
done
for pathname in $dir0/macu/*/*HHZ; do
cp "$pathname" "data/$( basename "$( dirname "$pathname" )" )MACUHHZ"
done
cd $dir0/data
mkdir 2019.0{10..31}
mkdir 2019.00{1..9}
If there is also another way of executing the part of the code where I take the files so I can generalize for several stations that would be nice, since I am only working with two stations right now but in the future I'll work with more.
Here is the tree to where the data is
macu
├── 2019.001
│   └── MACUHHZ
├── 2019.002
│   └── MACUHHZ
├── 2019.003
And
stam
├── 2019.001
│   └── STAMHHZ
├── 2019.002
│   └── STAMHHZ
├── 2019.003
│   └── STAMHHZ
So ideally the final situation would be:
data
├── 2019.001
│   ├── 2019.001MACUHHZ
│   └── 2019.001STAMHHZ
And so on

Answer 1

The script below creates the wanted file structure. The top level directories from which you want to copy data (in your example macu and stam) should be added to the top_dir variable. You can also change it to use a wildcard, or read them from a file, etc.
The basic idea is simple: For each top level directory, for each data directory, create the corresponding directory in data, and for each file, copy the file.
pushd and popd are used as a simple hack to make the * wildcards do what we want. $dir0 contains the root folder of the operation, so we always know where data is.
set -e is used to exit immediately if there is an error.
#!/bin/bash
set -e
top_dirs=( macu stam )
dir0="$(pwd)"
mkdir -p data
for dir in "${top_dirs[#]}" ; do
pushd "$dir" >/dev/null
for datadir in * ; do
mkdir -p "$dir0/data/$datadir"
pushd "$datadir" >/dev/null
for file in *HHZ ; do
cp "$file" "$dir0/data/$datadir/$datadir$file"
done
popd >/dev/null
done
popd >/dev/null
done