From the ITF website today:
2021 ITF Seniors (50-55-60) World Team & Individual Championships (updated 26 October)
Due to the ongoing impact of the Covid-19 pandemic, the ITF Seniors (50-55-60) World Team & Individual Championships will not be held as scheduled in Boca Raton & Palm Beach Gardens, USA in April-May 2021. Further information will be provided as soon as possible.
The dates of the Young Seniors and Super Seniors World Championships are as follows:
2021 World Team and Individual Championships
2021 ITF Young Seniors (35-40-45) World Team & Individual Championships
The 2021 ITF Young Seniors (35-40-45 years) World Team & Individual Championships will take place in Umag, Croatia from Sunday 12 September – Saturday 25 September 2021.
2021 ITF Super-Seniors (65-70-75-80-85) World Team & Individual Championships
The 2021 ITF Super-Seniors (65-70-75-80-85 years) World Team & Individual Championships will take place in Mallorca, Spain from Sunday 10 October – Saturday 23 October 2021.
Factsheets for these events will be made available approximately 6 months before the event takes place.