This is WhatsHap 2.8 running under Python 3.9.23
[W::hts_idx_load3] The index file is older than the data file: Sig_18_tissue.recal.bam.bai
[W::hts_idx_load3] The index file is older than the data file: Sig_18_tissue.recal.bam.bai
[E::idx_find_and_load] Could not retrieve index file for 'input_filtered.vcf.gz'
[E::idx_find_and_load] Could not retrieve index file for 'input_filtered.vcf.gz'
[E::idx_find_and_load] Could not retrieve index file for 'input_filtered.vcf.gz'
Working on 2 samples from 2 families

# Working on contig chr21 in individual Sig_18_Blood
Found 0 usable heterozygous variants (0 skipped due to missing genotypes)
WARNING: Sample 'Sig_18_Blood' not found in any BAM/CRAM file.
Found 0 reads covering 0 variants
Kept 0 reads that cover at least two variants each
Selected 0 most phase-informative reads covering 0 variants
Best-case phasing would result in 0 non-singleton phased blocks (0 singletons). 
Phasing 1 sample by solving the MEC problem ...
No. of phased blocks: 0

# Working on contig chr21 in individual Sig_18_tissue
Found 481 usable heterozygous variants (0 skipped due to missing genotypes)
[W::hts_idx_load3] The index file is older than the data file: Sig_18_tissue.recal.bam.bai
Number of supplementary alignments: 0
Number of non-singleton groups: 87232
Skipped 0 groups
Found 232060 reads covering 481 variants
Kept 65997 reads that cover at least two variants each
Selected 1419 most phase-informative reads covering 271 variants
Best-case phasing would result in 93 non-singleton phased blocks (0 singletons). 
Phasing 1 sample by solving the MEC problem ...
Largest block contains 12 variants (4.4% of accessible variants) between position 44573789 and 44592106
WARNING: Ignoring existing phasing information found in input VCF (PS tag exists).

# Resource usage
Maximum memory usage: 0.441 GB
Time spent reading BAM/CRAM:                   64.4 s
Time spent parsing VCF:                         0.0 s
Time spent selecting reads:                     3.1 s
Time spent phasing:                             0.8 s
Time spent writing VCF:                         0.0 s
Time spent finding components:                  0.0 s
Time spent on rest:                             0.4 s
Total elapsed time:                            68.8 s