This is WhatsHap 2.8 running under Python 3.9.23
[W::hts_idx_load3] The index file is older than the data file: 1136_8DK-T1-TDNA-1_B23VCL7LT4_1.recalibrated.bam.bai
[W::hts_idx_load3] The index file is older than the data file: 1136_8DK-T1-TDNA-1_B23VCL7LT4_1.recalibrated.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
WARNING: Skipping duplicated position 31276691 on chromosome 'chr13' Hiding further warnings of this type, use --debug to show

# Working on contig chr13 in individual 1136_8DK-N1-BDNA-1_B23KFG5LT4_1
Found 51 usable heterozygous variants (0 skipped due to missing genotypes)
WARNING: Sample '1136_8DK-N1-BDNA-1_B23KFG5LT4_1' 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 chr13 in individual 1136_8DK-T1-TDNA-1_B23VCL7LT4_1
Found 402 usable heterozygous variants (0 skipped due to missing genotypes)
[W::hts_idx_load3] The index file is older than the data file: 1136_8DK-T1-TDNA-1_B23VCL7LT4_1.recalibrated.bam.bai
Number of supplementary alignments: 0
Number of non-singleton groups: 40404
Skipped 0 groups
Found 99789 reads covering 402 variants
Kept 16703 reads that cover at least two variants each
Selected 627 most phase-informative reads covering 162 variants
Best-case phasing would result in 41 non-singleton phased blocks (0 singletons). 
Phasing 1 sample by solving the MEC problem ...
Largest block contains 55 variants (34.0% of accessible variants) between position 25096615 and 25097712
WARNING: Ignoring existing phasing information found in input VCF (PS tag exists).

# Resource usage
Maximum memory usage: 0.302 GB
Time spent reading BAM/CRAM:                   77.5 s
Time spent parsing VCF:                         0.0 s
Time spent selecting reads:                     0.6 s
Time spent phasing:                             0.4 s
Time spent writing VCF:                         0.0 s
Time spent finding components:                  0.0 s
Time spent on rest:                             0.2 s
Total elapsed time:                            78.8 s