Large scale projects and a tight timeline- definitely is a nightmare for UX designers…
But there are few concepts which could help.
Templatize and Reuse
Steps:
1. Identify use-cases which are similar E.g. Initiate a new Entity
2. Identify UI components which can cater to use-case requirements
3. Define a UI pattern/Template which can accommodate task flows across identified use-cases
4. Mark and label sections in the template
5. Define a Data Dictionary mapping sections in the Template