Hi Divya,

There are at least 2 ways to do this.

Let's start with the easiest. Option 1:

• From the modeler with your project open, you're going to create a branch from rev455. Here's how:
  • Find the Team menu, and select "Manage Branch Lines"
  • Click the "New" button
  • Follow the prompts to select revision 455 and create the branch
  • It will open in the modeler as a separate working copy
  • Here is documentation of the feature: https://docs.mendix.com/refguide/create-branch-line-dialog

Option 2 is done using TortoiseSVN and is more manual. If you're not familiar with SVN or Tortoise in general, stick with option 1. Otherwise:

• Install TortoiseSVN 1.7 (not 1.8 or 1.9, this is important)
• Close the project in the modeler
• From windows explorer, right-click your project directory and choose TortoiseSVN -> Update to revision
• Choose your revision and make sure you select the recursive option so that all files are updated to the correct revision
• Open the project again

Do you want to access it locally or build a package in the cloud?

locally, you can use the “reverse merge changes” feature. Download a copy of your mainline, go to the team tab > reverse merge changes. From here you can select a commit or a range of commits that you want to “reverse”. So in this case select revision 456 as your start and 459 as your end. Next the modeler will download those revisions and create the reverse of them. If you want to make these changes permanent you can commit them. 

Alternatively, you can create a branch line from revision 455. Go to the team tab > manage branch lines. From here you can create a branch from your mainline and select which revision to create it from

For the cloud, when you build a package you can select a development line and certain revision to build off of.

hope this helps!