`summarymodify` error when new label has `:` in it

When I run summarymodify with the following command line:

$ summarymodify --samples samples/posterior_samples.h5 --webdir ./modified --labels A4-PhenomHM:C01:IMRPhenomHM E2-PhenomPv3HM:C01:IMRPhenomPv3HM I5-PhenomPv2:C01:IMRPhenomPv2 I6-PhenomD:C01:IMRPhenomD SEOBNRv4HM_ROM:C01:SEOBNRv4HM_ROM SEOBNRv4P:C01:SEOBNRv4P SEOBNRv4PHM:C01:SEOBNRv4PHM SEOBNRv4_ROM:C01:SEOBNRv4_ROM

I get the following warnings:

2020-03-24  17:34:08 PESummary WARNING : Unable to find label 'A4-PhenomHM:C01' in the root of the metafile. Checking inside the groups
2020-03-24  17:34:08 PESummary WARNING : Unable to find label 'E2-PhenomPv3HM:C01' in the root of the metafile. Checking inside the groups
2020-03-24  17:34:08 PESummary WARNING : Unable to find label 'I5-PhenomPv2:C01' in the root of the metafile. Checking inside the groups
2020-03-24  17:34:08 PESummary WARNING : Unable to find label 'I6-PhenomD:C01' in the root of the metafile. Checking inside the groups
2020-03-24  17:34:08 PESummary WARNING : Unable to find label 'SEOBNRv4HM_ROM:C01' in the root of the metafile. Checking inside the groups
2020-03-24  17:34:08 PESummary WARNING : Unable to find label 'SEOBNRv4P:C01' in the root of the metafile. Checking inside the groups
2020-03-24  17:34:08 PESummary WARNING : Unable to find label 'SEOBNRv4PHM:C01' in the root of the metafile. Checking inside the groups
2020-03-24  17:34:08 PESummary WARNING : Unable to find label 'SEOBNRv4_ROM:C01' in the root of the metafile. Checking inside the groups

Even though A4-PhenomHM is in the original result file.