This is via analysis from ING (in summary from a longer note)

Our base case:

  • The ECB ends net asset purchases in the second quarter of 2022 and starts hiking interest rates by 25bp in September with another 25bp in December.
  • A new asset purchase programme will be announced to tackle any unwarranted widening of spreads across eurozone countries.

Earlier and more aggressive normalisation:

  • inflation stays higher for longer and longer-term inflation expectations scare the ECB so much that it ends net asset purchases in June and hikes interest rates by 25bp in July with another 25bp in September.
  • Alternatively, and given that the ECB prefers to link important decisions to new economic forecasts, the central bank could start hiking rates with a 50bp move in September.

The fear is back move:

  • the economic outlook worsens further, core inflation forecasts start to fall and wage growth disappoints on the back of rising unemployment. The ECB still sticks to normalisation, hikes rates by 25bp in September and December but delivers no further rate hikes. Instead, slowing credit growth and capital flight out of the eurozone forces the ECB to restart net asset purchases, combined with new Targeted Longer-Term Refinancing Operations.