Hbase FilterList as MUST_PASS_ONE with two RowFilters returns everything

I have a column family called odds_api with the number of rows with the rowkey: /bt=??/bm=??/mk=??/se=??:

/bt=1/bm=MN/mk=344/se=23394/odds_api
/bt=1/bm=BY/mk=344/se=23394/odds_api
/bt=1/bm=SN/mk=344/se=23394/odds_api
/bt=1/bm=BB/mk=344/se=23394/odds_api
/bt=1/bm=SF/mk=344/se=23394/odds_api
/bt=1/bm=XY/mk=344/se=23394/odds_api

I want to filter based on a list of bm values aka filter based on bm=SF,BB,MN.

To do this I created a filterList of MUST_PASS_ONE with 1 to many rowFilters (depending on how many values the user requests)

public ResultScanner scan(String id , List<String> bms) throws BigTableGetException {
    try{
        Table table = connection.getTable(TableName.valueOf(this.tableName));
        Scan scan = new Scan();
        scan.addFamily(Bytes.toBytes("odds_api"));
        FilterList mainFilterList = new FilterList(FilterList.Operator.MUST_PASS_ONE);

        bms.stream()
                .forEach(bm -> {
                    mainFilterList.addFilter(new RowFilter(CompareOp.EQUAL, new RegexStringComparator("/bt="+id+"/bm="+bm+".*")));

                });
        System.out.println("this is the filter list " + mainFilterList.toString());

        scan.setFilter(mainFilterList);
        return table.getScanner(scan);
    }catch (IOException ex){
        throw new BigTableGetException("Failed to get rows in BigTable", ex);
    }
}

(I know -- pointless stream for a forEach!)

This works fine when only one bm is specified, print statement:

this is the filter list FilterList OR (1/1): [RowFilter (EQUAL, /bt=1/bm=B4.*)]

however if more than one is specified then it returns everything, print statement:

this is the filter list FilterList OR (2/2): [RowFilter (EQUAL, /bt=1/bm=B4.*), RowFilter (EQUAL, /bt=1/bm=PP.*)]

In fact, if I enter two or more 'incorrect' bm values it still returns everything!

I have read: https://www.oreilly.com/library/view/hbase-the-definitive/9781449314682/ch04.html

I have also tried to move the bt=? filter out to a separate MUST_PASS_ALL filter and then have another list of row filters for bm=?

this is the filter list FilterList AND (2/2): [FilterList AND (1/1): [RowFilter (EQUAL, .*bt=1)], FilterList OR (2/2): [RowFilter (EQUAL, .*/bm=B4.*), RowFilter (EQUAL, .*/bm=PP.*)]]

Same problems.

I must be missing something obvious, any help would be greatly appreciated.

hbase versions:

<dependency>
    <groupId>com.google.cloud.bigtable</groupId>
    <artifactId>bigtable-hbase-1.x</artifactId>
    <version>1.4.0</version>
</dependency>

<dependency>
    <groupId>com.google.cloud.bigtable</groupId>
    <artifactId>bigtable-hbase-1.x-hadoop</artifactId>
    <version>1.4.0</version>
</dependency>

Have you considered using a single regex? "/bt=FOO/bm=(A|B|C|D).*" should work.

Also, please raise an issue in https://github.com/GoogleCloudPlatform/cloud-bigtable-client. There does seem to be a bug somewhere in the client code.