docs: update oid deprecation migration

docs/upgrade-to-v5.md

@@ -89,12 +89,17 @@ This library no longer polyfills [ES Map](https://developer.mozilla.org/en-US/do
 The following deprecated methods have been removed:
 
 - `ObjectId.prototype.generate`
- - Instead, generate a new ObjectId with the constructor: `new ObjectId()`
+ - Instead, generate a new ObjectId with the constructor: `new ObjectId()` or using the `static generate(time?: number)` method.
+- `ObjectId.prototype.generationTime`
+ - Instead, use `static createFromTime()` and `getTimestamp()` to set and inspect these values on an `ObjectId()`
 
 - `ObjectId.prototype.getInc`
 - `ObjectId.prototype.get_inc`
 - `ObjectId.get_inc`
- - The `static getInc()` is private now since it has a side effect of changing the value of the next `ObjectId` generated, using `new ObjectId()` and inspecting the increment section of the bytes can provide insight into the current increment value.
+ - The `static getInc()` is private since invoking it increments the next `ObjectId` index, instead users should inspect the counter on newly created ObjectId if it is needed.
+ - See the following code snippet for how to obtain the counter field of an ObjectId:
 
-- `ObjectId.prototype.generationTime`
- - Instead, use `static createFromTime()` and `getTimestamp()` to set and inspect these values on an `ObjectId()`
+```ts
+const oid = new ObjectId();
+const counterField = oid.id[9] << 16 | oid.id[10] << 8 | oid.id[11];
+```